/Engine/Plugins/Online/OnlineSubsystem/Source/Public/Interfaces/OnlineSessionInterface.h
Removes a player from the session.
virtual void RemovePlayerFromSession ( int32 LocalUserNum, [FName](API\Runtime\Core\UObject\FName) SessionName, const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & TargetPlayerId )